Liner for gun barrels



Sept. 2, 1947. J. P. MAGOS LINER FOR GUN BARRELS Filed Nov. 27, 1944 2 Sheets-Sheet l p 2,1947- 7 2. P. MA-Gos. 2,426,972

LINER FOR GUN BARRELS Filed Nov. 27, 1944 Sheets-Sheet 2 J5 Z3 ,jizveia 21- J71? JzvMyos:

Patented Sept. 2, 1947 ATE/NT OF E ICE 2,426,972 LINER FOR GUN'BARRELS John P.- Magos, Wilmette, Ill., assignorto Crane (30., Chicago, Ill., a corporationiof Illinois- Applicationv November 2'1, 1944, Serial No. 565,255

1: Claim. 1

This invention relates to liners for gun barrels or the like. More particularly, it relates toa novel typeof liner in which the relative ease of renewability and economyof construction are significant features. In order to acquire a better understanding of the background concerning my invention, it should be-understoodthat the bores of guns made of the usual materialswhen fired for an extended period become severely eroded in a region extending from the commencement of the-rifiing to about four calibers beyond. The erosion of the bore results in subsequent decreased velocity, accuracy and range and, after a time, the barrel must be discarded. There have been numerous methods suggested for remedying this situation such as the insertion of short replaceable liners positioned in that portion of the gun where. the erosionrismost severe, but, to my knowledge, most of these constructions have been, more. expensive, less easy; to, accomplish the replacement and considerably more difficult to remove when. replacement. has become necessary. The latter difficulty is especially significant when it is realized that repairs and re-. placementsare frequently made in the fieldunder emergency conditions and where suitable tools and equipment may be lacking.

Difflculties. encountered with the designs previously referred. to. have led to the development of a design which it is. believed overcomes all previous difficulties and in addition possesses many advantages over those previously tried. A further important object, is, tov provide a liner having a substantially circular taper over its entire length and which preferably employs a flange at its breech end, the latter being held securely to the gun barrel by means of suitable holding means, the latter serving not only to hold the liner within the barrel, but also aiding in the removal of the liner for repairs and inspection.

A further important object is to provide a holding means in which the latter serves also as an index and guide in assuring proper and accurate alignment of the liner and its rifling with the rifling of the barrel and which is preferably so designed that such positioning of the liner cannot be incorrectly inserted.

Another important object is to provide for a flanged renewable liner in which the end limits are adequately protected against injury in the course of handling the barrel and liner assembly.

A still further important object is to provide a flanged type of liner which may either be of the same material as the barrel, or which may acteristics suchas a metal. alloy or composition consisting of cobalt and atleast two of themetals of the chromium group. Or the liner itself may be completely constructed of such desirable metal or composition;

Other objects and advantages of the design of the instant invention lieinthe relative ease of manufacture, greater accuracy in machining, elimination of substantial clearances between the liner and. barrel and the relative ease in which the latter members may be assembled and disassembled. These and other advantages will be more clearly brought out inproceeding; with the specification read in light of theaccompanying drawings, in which Fig. 1 is a sectional assembly View of a gun barrel and liner embodyingmy invention.

Fig. 2' is an enlarged fragmentary sectional view of the end portion of the assembly described in connection with Fig. 1-.

Fig. 3 is an endview showing the flanged portion and bolting arrangement of the liner in its assembly with the barrel shown in- Figs. 1 and 2'.

Fig. 4 is a sectional view of a modified form of liner.

Fig. 5- is a sectional view of the modified form of Fig. 4 taken on the line 5-5 of Fig. 4.

Fig; 6 is a further modified form of the invention, in which the linerend'portionis enclosed.

Referring now to Fig. l, the gun barrel; I is provided with a suitably tapered bore 2' within which the similarl tapered liner 3 is fitted, form ing with the barrel la gas sealed joint, as indicated by the tongue and groove joint as at 4, to accommodate the annular beaded end 5 of the liner 3. The end portion 5 may be rounded as shown to fit snugly within the receiving groove but the form described is not absolutely essential.

Directing attention now to the breech end of the gun barrel, the liner 3 is provided with a flange 6, the latter member being held to the gun barrel by means of the bolts 7. The latter members are positioned so as to extend through the counterbored holes 8 in the flange and to engage the threads of the tapped holes 9 in the end of the gun barrel I. The bolts as shown in Fig. 2 are preferably distributed uniformly around the flange so that the tightening of the liner within the barrel may be done gradually and uniformly around the bolt circle. In lining up the rifiing ll of the liner accurately with the rifling l2 of the barrel, one bolt or, if desired, two of the bolts preferably diametrically opposite one or several be lined with ametal having desirable wear chartapped holes 9 may be of an odd size and form so as to assure the correct positioning of the liner within the barrel, considering especially the location of the rifling. A longer tapped hole I3 is illustrated in Fig. 1 as an example of one way in which a pilot or dowel bolt (not shown) may serve the function of guiding the liner in its course of assembly with the barrel l In connection with allowing for the convenient removal of the liner 3, it should be noted, as shown more clearly in Fig. 3, that a number of tapped holes are preferably spaced alternately between the holes 8 which are preferably counter-- bored as indicated. The tapped holes Ht have fOr their purpose the provision of means for allowing the bolts 1 to be removed irom thebarrel engaging posiiton shown in Fig; 1- t'o threadedly' engage the tapped holes of. the liner 6.v The bolts 1 then bear against the end of the barrel l as shown in Fig. 2 upon suitable rotation. Thiis the easy removal of the liner 3 is accomplished. It will: be apparent now thatthe liner may be ex.- tracted from the barrel I by simply transferring the' bolts 1 from the holes 8 and the respective tapped holes 9* to the tapped holes Ml inthe flange: Each bolt is successively tightened. evenly against the end 2E1 of the barrel, thereby forcing the flange 6 away front the barrel to extract the liner. It willbeapparent that the complete assembly provides for a substantial-'- frictional surface contact along the taper of the liner for virtually the entire length of the latter member-.- This is desirable not only inpreventing. any tendency to turn during the action of the projectile leaving the barrel butit also supp'Grtsthe liner adequately against any outward distortion because of the complete surface support provided by the inner portion of the gun barrel itself.-

Whi-le the foregoing description. has concerned itself with; a; construction using? a substantially unbroken taper in the liner in: may be desirable to prevent undue torque otherwise tending to cause the rotation of the liner within the barrel by other means-.- A modified form of construe tion may be employed in which the liner 3a shown in Fig. 4 may be tapered for a relatively short portion of its length, as indicated at I4. As shown more clearly in; the sectional View of Fig. 5, the end portion of the liner adjacent its: flange 6 may be of oval cross-section. Otherwise the construction including the/ taper is'similar to that employed inl 'igs. 1 and 2; but the liner may be oval in formto further act as asafeguard against rotation. 'lfhe tapped holes 24' forremoval oi the liner may beused,- with the counterboredz holes 22 employed for the purpose of securing the liner within the barrel, the latter member being tapped as at 23. For suitable assembly with a carriage (not shown) the gun barrel I may be threaded as indicated at l5.

In order that the flange 6 may be protected, it may be desirable as shown in Fig. 6 to counterbore the barrel 1 as at [8, with the flange shoulderi ng as at [9iv The bolts I"! are used to draw the flange and liner 3b" inwardly toward the barrel to make the desired seat.

It should be apparent that numerous modification-s may be made without departing from the spirit of the invention as expressed in the claim appended heretot' I claim 1' A gun barrel construction, the combination including a barrel, a tapered liner therefor, means for retaining the said liner in substantially immovable position relative to the said barrel, the said; retaining means including a flanged retaining member constituting an integral end portion oi the said liner, the said retaining member having annular spaced apart threaded and unth-r'eaded apertures; having annularly positioned bolt means: for engagement with the urn threaded-1 apertures and with the end of the said barrel toholdthe said liner in substantially axially immovable position relative to the barrel, the said bolt means being removable to cooperate with the threaded apertures of the said. flanged retaining member whereby upon annular repositioni-ng of the said bolt means in the threaded aperture tobear' against a transverse end surface of the said barrel the said. liner is axially movable relative to the barrel for replacement or repair.

JOHN P. MAGQS;

REFERENCES CITED The foilbwing references are of record in: the file of this patent:

UNITED STATES PATENTS Number Name Date 1,804,935 J acobus a May 112,. 1=931 676,649 Kline a an June 1 8;. 1961 15,757,257 McCam'i May 6;. I930 329,193 Wheeler i Nov. 3, 1885 2,337,021 Barbieri a Dec. 21, 1943 1,355,421 P'eders'en Oct. 12, 1920 2,007,811 Or'elind: Jilly 9', 1935 2,278,625 Traylor et al' l Apr. 7,. 1942 

